As I could understand, it seems like you are having problems with your unit as the screen seems to be flickering. I apologize for any inconvenience this may be causing.

Regarding this problem, there are several steps we can try to follow:

1) Please try a different cable when connecting the unit.2) Please try a different interface for example the mini display port or HDMI.3) Please try a different monitor to check if it is a monitor or Nuc issue.4) If the graphics driver is not updated, please try updating it to the version 4849: